Date Columns in Excel Add-on

I’m trying to build out a booking Tape Chart that would show rows of properties with a range of dates as columns. I hope to be able to conditionally color each cell if there is a booking for a given property on a date. I’ve been trying to build this using the Excel Add-on.

My question is how do I generate the date columns across the top row? I realize I’ll need to create a type of button or picker to use for the beginning date (and the number of days to show in the future), but for now, I just want to know what to input into the Excel Type of Content and Data source in order to generate columns of dates, say from today + 90 days.

Then I can move toward dynamically selecting the start and end dates to generate, as well as finding the bookings that match.